Adjustable twin dental handpiece



June 5, 1962 s. KTARIAN ETAL 3,037,282

ADJUSTABLE TWIN DENTAL HANDPIECE Filed Nov. 2l, 1958 vr e2 sa SmzmsAwvmzmm E/ BY ANAS-mss ossmms QWAMMLMM AWTCQNEYS i' arent ffice3,037,282 Patented June 5, 1962 3,037,282 ADJUSTABLE TWIN DENTALHANDPIECE Sarkis Aktarian, and Anastase Iossifidis, both of 722 DeLepee, Outremont 8, Montreal, Quebec, Canada Filed Nov. 21, 1958, Ser.No. '775,571 9 Claims. (Cl. 32-27) This invention relates to an improvedtwin dental handpiece having improved means for adjusting twininstrument-holding rotors relative to each other.

The primary object of the invention is to provide a more efficient andaccurately operating device of the character indicated which has arelatively stationary drive rotor and a floating driven rotor, an idlerrotor being operatively engaged with both rotors, and bearing meansengaged with the floating rotor whereby the iloating rotor is positivelyand at all times maintained with its rotational axis parallel to that ofthe stationary rotor in any adjusted position of the iioat-ing rotor,and the speed `and direction of rotation of the iloating rotor arepositively maintained at the same rate and in the same direction asthose of the stationary rotor, so that dental instruments secured in therotors can drill or grind identically and on parallel axes in one or twoadjacent teeth, as in providing for three-quarter crowns, in parallelslot cutting, in making parallel pin holes for pin-ledge inlays, and inrearning root canals in adjacent teeth for crowns having posts solderedtogether.

Another object of the invention is to provide a device of the characterindicated above wherein the idler roller is free to move laterally tomaintain full driving contacts with the drive and driven rotors, and hasspring means for so positioning the idler roller in all of the adjustedpositions of the driven roller.

A further object of the invention is to provide a device of thecharacter indicated above wherein there is provided threaded adjustingmeans on the body of the handpiece which is connected to the rollerdetent spring for adjusting the same endwise so Vas to adjust .thedriven roller toward and away from the drive roller, through an inniterange of adjustments, while the device is in operation.

Other important objects and advantageous features of the invention willbe apparent from the following description and the accompanyingdrawings, wherein, for purposes `of illustration only, a specific formof the invention is set forth in detail.

In the drawings:

FIGURE l is a side perspective view of a device of the invention;

FIGURE 2 is an enlarged top plan view of FIGURE l;

FIGURE 3 is a vertical longitudinal section taken on the line 3--3 ofFIGURE 2;

FIGURE 4 is a fragmentary horizontal section taken on the line 4-4 ofFIGURE 3, showing the positions of the rotors and the idler roller withthe driven roller moved away from the drive roller;

FIGURE 4a is a view similar to FIGURE 4, showing the said positions whenthe driven roller is moved toward the drive roller;

FIGURE 6 is a fragmentary transverse vertical section taken on the line6 6 of FIGURE 3;

FIGURE 7 is a fragmentary horizontal section taken on the line 7--7 ofFIGURE 3; and

FIGURE 8 is an enlarged fragmentary vertical transverse section taken onthe line 8--8 of FIGURE 3.

Referring in detail to the drawings, wherein like numerals designatelike parts throughout the several views, the illustrated devicecomprises a longitudinally elongated, generally rectangular case 16having forward and rear ends 12 and 14, respectively. A longitudinallyelongated and generally rectangular chamber 16 opens through the topsurface 18 of the case 16, and a removable cover plate 20 is secured, asindicated at 22 upon the surface 18. A longitudinal tubular shank 24ha-s on its forward end a boss 26 which is threaded, as indicated at 28through the rear end of the case 10. A flexible shaft 3l) extendsforwardly through the shank 24 and has a bearing 32 turning in the shankand carrying a forwardly facing crown gear 34 which extends into therear end of the chamber 16. A portion of the shank 24 spaced rearwardlyfrom the case 10 is threaded, as indicated at 36, for a rotary adjustingknob 38, circumposed on the shank 24 and having a peripheral groove 40in which is sidewise and removably engaged a lateral hook 42 on the rearend of a longitudinally elongated roller detent spring 44.

The spring detent 44 extends spacedly and forwardly along the case coverplate 26, and a headed guide and pivot pin 46 threaded in the coverplate 20 and the upper surface of the case 1t) at the rear ends thereof,extends through a longitudinal slot 48 in an intermediate part of thedetent 44, the slot 48 permitting pivoting of the detent 44 on the pin46 for disengaging the hook 42 from the adjusting knob groove 40, andlongitudinal `adjustments of the detent in opposite directions, by meansof the knob 38.

The forward end of the detent 44 is widened to dene a flat head St)having a longitudinally elongated notch 52 in the side edge S4. Formedin the edge 54 forwardly of the notch 52, are rear :and forwardtransverse slots 56 and 58, respectively. The slot 56 has positioningengagement with the groove of a dental burr, as hereinafter describedfor the dual purpose of holding its driving rotor in its paths of linearmovements and retaining the burr in its rotating axis.

The spring detent 44 overlies the usual spring detent 60 which ispivoted on the pin 46 and has at its forward end a side slot 62 engagingin the groove 120 at the upper end of a dental burr 98 engaged in avertical axis roller 66, which is stationarily journaled at its lowerend in the bottom wall 68 of the chamber 16 and has a crown gear 7 0which is in mesh with the crown gear 34, and is thereby driven by thecable 30.

A slot 72 is formed in the chamber bottom Wall 68 forwardly of thestationary roller 66, and is longitudinally elongated, and has a forwardend '74, terminating in rearwardly spaced relation to the forward endwall 76 of the chamber 16. The forward end wall, as seen in FIGURES 4and 5, is composed of a concave recess portion 78 in line with theroller 66 and a flat straight portion 80 at one Side of the concaveportion 78.

A floating bearing or follower 82 comprises a vertically elongated block84 having a convex forward side 86 to t the recess 78 and a concave rearside 88, and having on its upper end a forwardly offset and upstandinglug 90. The lower end 92 of the follower block 84 rests slidably upon aledge 94 which extends along the sides and the forward end of the slot'72 on a level below the top of the bottom wall 68, as shown in FIGURE3, with the upper end of its lug 98 rising above the'upper surface 18 ofthe case l0 and through the slot S8 in the detent head 50.

A ilo-ating and adjustable driven roller 96 has a tubular vertical bodyto accept a dental instrument, such as a burr 98, yand has thereon, on alevel immediately above the upper end of the follower block 84, anannular shoulder or land 108. The upper part of the roller 96 isslidably journaled in a longitudinal slot l1011 in the cover plate 20.The upper end of the follower lug is engaged through the forward slot 58ltherein and acts to relieve side loading between the slot 56 and thegroove 126 of the related burr 9S.

It is obvious from the foregoing that lengthwise adjustment of thedetent 44 by rotating the knob 38 on o a the shank 24 adjusts the detent44 endwise and thereby moves the driven roller 96 and the forward burr93 toward and away from the drive roller 66 in a longitudinalrectilinear path.

The rollers 66 and 96 have circumferential bearing grooves 67v and 97near their upper ends in which are engaged annular retainers 69 and 99which are conned in undercuts 103 in the bottom of the cover plate 20along the sides of the slot 101 therein.

Positioned in the chamber 16 at one side of and constantly frictionallyengaging the two rollers 66 and 96 is a vertical friction idler roller104, preferably formed of suitable material such as nylon, and havingpintles 106 on its upper and lower ends, on which are circumposed theeyes 108 at the intersections of the divergent arms 110 of V-shapedsprings 112. The spring arms 1x10 terminate in curved terminals 114which are slidably confined in upper and lower longitudinal positioningand retaining grooves 116 in the side 1118 of the chamber 16, wherebythe idler roller 104 is constantly and forcibly engaged with and betweenthe outer surfaces of the crown gear 70 on the stationary roller 66 andthe land 100 on the adjustable roller 96, as shown in FIGURES 4 and 5,during all approached or distanced positions of the adjustable roller 96relative to the stationary roller 66, so that the rollers are driven atthe same speeds and in the direction with the axes of the rollers beingmaintained parallel to each other.

When the adjustable driven roller 96 is to be removed, the detent 44 ispivoted sidewise in order to disengage its hook 42 from the adjustingknob groove 40. This removes the rear and -forward slots 56 and 58, fromengagement with the groove of the floating burr and from the follower82. 'I'he cover 20 when removed permits removal and replacement in thechamber 16 of the rol- 1ers and burrs.

Standard burrs 98, which as illustrated herein, have annular grooves 120at their upper ends which are rotatably received in the slots 56 and 62,and chordal ilats 122 at one side thereof below the grooves 120 whichprovide shoulders 124. The rollers 66 and 96 have on their upper endslateral lugs `126 which bear upon the shoulders 124 and against theflats 122 so as to lock the burrs in place in the `rollers and againstrotation relative to the rollers.

Although there has been shown and described herein a preferred form ofthe invention, it is to be understood that the invention is notnecessarily confined thereto, and that any change or changes in thestructure of and in the relative arrangements of components thereof larecontemplated as being within the scope of the invention as defined bythe claims appended hereto.

What is claimed is:

1. An adjustable twin dental handpiece comprising a case, a relativelystationary instrument accepting drive roller journaled in the case,driving means connected to the drive roller, a longitudinally adjustableinstrument accepting driven roller rotatably and slidably mounted in thecase for adjustments toward and away from the drive roller in arectilinear path with the axes of the rollers parallel to each other andin the same plane, a floating friction idler roller mounted in the caseand bearing against the drive and driven rollers and springpressedtoward the drive and driven rollers, a detent mounted on the case andconnected to said adjustable driven roller, and an adjusting knobmounted on the case and connected to the detent for imparting selectedendwise adjusting movements to the detent and the driven roller.

2. An adjustable twin dental handpiece according to claim l, whereinsaid case has a tubular longitudinal shank fixed `on one end thereof,said knob being threadably circumposed on the shank, said detent havinga hook on one end operatively engaged with said knob,

3. An adjustable twin dental handpiece according to claim 1, wherein afloating longitudinally movable follower is disposed in the case at theside of the driven roller remote from the drive roller and isoperatively connected to said detent.

4. An adjustable twin dental handpiece Comprising a case having rear andforward ends and an upper wall, a longitudinal chamber in said caseopening through said upper wall and having a chamber bottom wall, acover plate covering the chamber opening and removably secured upon saidupper wall, a headed guide and pivot pin traversing said cover plate andsecured to the case, an elongated spring detent having a longitudinalslot intermediate its ends engaged on said pin, said detent having rearand forward ends, a lateral hook on the rear end of the detent and ahead on the forward end of the detent, said head overlying the coverplate, an axial tubular shank having a forward end secured to the rearend of the case and having a threaded portion intermediate its ends, anadjusting nut threadably circumposed on said threaded portion -andhaving a peripheral groove in which said hook is sidewise and removablyengaged, a rotary cable extending through said shank and terminating atits forward end in a forwardly facing crown gear journaled in the rearend of the case and exposed in said chamber, a vertical relativelystationary tubular drive roller removably journaled at its lower end insaid chamber bottom wall, said chamber having rear and forward endwalls, the drive roller being located near said rear end wall and havinga crown gear in mesh with the cable crown gear, said detent head havinga side edge formed with a rear transverse slot and a forward transverseslot, said bottom wall having therein a longitudinal slot extendingforwardly from said drive roller, and said cover plate having alongitudinal slot registered with the bottom wall slot, a verticaladjustable tubular driven roller, said driven roller having a lower partjournaled in said bottom slot and having an upper end extending throughthe cover plate slot, separate bearing means journaled on the upper endsof the drive and driven rollers and slidably confined in said coverplate slot, a floating follower in Said chamber between said drivenroller and ythe forward end of the chamber and bearing against theadjacent side of the driven roller, said follower having a lower portionslidably confined in said bottom wall slot and an upstanding lug engagedin said forward transverse slot, front and rear dental burrsnon-rotatably engaged through said driven and drive rollers, said burrshaving upper ends rising above the rollers and provided withcircumferential grooves, said rear transverse slot of the detent headbeing engaged in the groove of the front burr, detent means on said casehaving a side slot engaged with the groove of the rear burr, rotation ofthe adjusting knob on the shank in opposite directions serving to movesaid follower and said driven roller relative to the drive rollerthrough the medium of said detent, a floating friction idler roller insaid chamber at one side of and between said drive and driven rollers,said chamber having a side wall provided with vertically spacedlongitudinal positioning grooves, said idler roller having pintles onits upper and lower ends, and expansion springs having eyes journalingsaid pintles and arms slidably confined in said positioning grooves,said springs being compressed between said side wall and the rollers andproducing constant frictional engagement of the idler roller with thedrive and driven rollers in all adjusted positions of the driven roller.

5. In an adjustable twin dental handpiece, a support, a stationaryinstrument accepting drive roller journaled on the support, anadjustable instrument accepting driven roller mounted on the support torotate relative to and to move longitudinally toward and away from thedrive roller with its axis parallel to the axis of the drive roller, afloating idler roller mounted on the support for movementslongitudinally and laterally relative to the rollers, spring meansacting between the support and the idler roller and holding the idlerroller operatively engaged lwith and between the drive and the drivenrollers, and adjusting means mounted on the support and operativelyconnected to the driven roller for moving the driven roller ltoward andaway from the drive roller under the tension of said spring means.

6. In an adjustable twin dental handpiece, a support, a stationaryinstrument accepting drive roller journaled on the support, anadjustable instrument accepting driven roller mounted on the support torotate relative to and to move longitudinally toward and away from thedrive roller with its axis parallel to 4the axis of the drive roller, ailoating idler roller mounted on the support for movementslongitudinally and laterally relative to the rollers, spring meansacting between the support and the idler roller and holding the idlerroller operatively engaged with and between the drive and the drivenrollers, and adjusting means mounted on the support and operativelyconnected to the driven roller for moving the driven roller toward andaway from the drive roller under the tension of said spring, and detentmeans connected to said adjusting means and to the support for holdingthe driven roller in an adjusted position.

7. In an adjustable twin dental handpiece, a support, a stationaryinstrument accepting drive roller journaled on the support, anadjustable instrument accepting driven roller mounted yon the support torotate relative to and to move longitudinally toward and away from thedrive roller with its axis parallel to the axis of the drive roller, ailoating idler roller mounted on the support for movementslongitudinally and laterally relative to the rollers, spring meansacting between the support and the idler roller and holding the idlerroller operatively engaged with and between the drive `and the drivenrollers, and adjusting means mounted on the support and operativelyconnected to the driven roller for moving the driven roller toward andaway from the drive roller under the tension of said spring, and detentmeans connected -to said adjusting means and to the support for holdingthe driven roller in an adjusted position, `said adjusting meanscomprising a follower mounted on said support for longitudinal movementtoward and away from the drive roller, said follower being engaged withthe side of the driven roller remote from the drive roller.

8. In lan adjustable twin dental handpiece, a support, a stationarydrive roller journaled on the support, an adjustable roller mounted onthe support and confined to longitudinal movement toward and away fromthe drive roller, a follower mounted on the support and engageable withthe side of the driven roller remote from the drive roller, a oatingidler roller mounted on the support for full longitudinal and lateralmovements relative to and located between and constantly operativelyengaged with the drive and driven rollers, spring means urging the idlerroller into engagement with the drive `and driven rollers, a detenthaving a rst end connected to the Afollower and a second end, and a knobthreaded on the support with which the second end of the detent isengaged.

9. In an adjustable twin dental handpiece, a support, a stationary driveroller journaled on the support, an ad justable roller mounted on thesupport and confined to longitudinal movement toward and away from thedrive roller, a follower mounted on the support and engageable with theside of the driven roller remote from the drive roller, a oating idlerroller mounted on the support for full longitudinal and lateralmovements relative to and located between and constantly operativelyengaged with the drive and driven rollers, spring means urging the idlerroller into engagement with the drive and driven rollers, a detenthaving a first end connected to the follower and a second end, and aknob threaded on the support with which the second end of the detent isengaged, means mounting said detent on the support and confining thedetent to endwise movement relative to the support, said driven rollerhaving an end journaled in said detent.

Chayes May 16, 1916 Fleischhacker Sept. 22, 1931

